The South is insisting North Korea provide guarantees to prevent any repetition of what Seoul insists was the unilateral closure of Kaesong by Pyongyang.

The North says it was not responsible, arguing that its hand was forced by hostile South Korean actions and intimidation – in particular a series of joint military exercises with the United States.

After the fourth round of talks last Wednesday, Kim said there was "a big difference" between the parties on working out a legal framework to prevent a future closure.

The South has proposed allowing foreign firms to operate there in the apparent belief that it would make it more difficult for the North to shut down the complex at will.

North Korea wants an unconditional and early restart of operations, and both sides have accused the other of lacking sincerity in the negotiating process.

Born out of the "Sunshine Policy" of inter-Korean conciliation initiated in the late 1990s by South Korean President Kim Dae-Jung, Kaesong was a crucial hard currency source for the impoverished North through taxes and revenues, and its cut of worker wages.

The joint complex, which had survived previous inter-Korean crises, was the most high-profile casualty of two months of elevated tensions that followed a nuclear test by the North in February that sparked international condemnation.

The North initially barred South Korean access to the zone, and then pulled out its workers. Seoul withdrew the last of its nationals in early May.

South Korean managers say they have suffered production losses of around $1 billion, and have criticised North and South Korea for playing political football with their businesses.

Some have threatened to pull out of the complex permanently unless operations resume soon.

The discussions on Kaesong followed a failed attempt to initiate high-level talks in June as military tensions subsided.

The dialogue was cancelled at the last minute because of a row over protocol, with neither side able to agree on the levels of their chief delegates.